Add theme into home and other screens UI

[nictjh]

This pull request introduces a major UI/UX overhaul for the home and live chat screens, focusing on a more modern, visually appealing design and improved user experience. The changes include the addition of gradient backgrounds, a redesigned header and chat interface, enhanced status indicators, and streamlined navigation. There are also minor code cleanups and improvements to navigation logic.

UI/UX Redesign

• [app/home.jsx]:
  Replaced the flat background with a LinearGradient, redesigned the header with a logo and bank name, improved the account and action cards, and consolidated profile and support actions into a single "Others" card. The "Support" button now opens the live chat. ]
• [app/LiveChatScreen.jsx]:
  Overhauled the chat interface with a gradient background, new header with logo and back button, improved status and queue indicators, redesigned chat bubbles with timestamps, and updated input and send/end buttons for better usability.

Navigation Improvements

• [app/home.jsx]:
  Updated navigation logic for "Support" and "View Profile" actions to use router parameters, ensuring proper data is passed to screens.
• [app/_layout.jsx]:
  Added a stack screen configuration for LiveChatScreen with the header hidden, matching the new design.

These changes collectively deliver a more polished, modern, and user-friendly banking app interface.

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This pull request also introduces a new single-agent live chat server using FastAPI and WebSockets, along with the necessary Docker and deployment configurations. It adds the main chat server implementation, a CLI agent for manual interaction, and supporting files to enable local development and containerized deployment. The changes are grouped below by theme:

Core server implementation:

• Added main.py, which implements a FastAPI-based WebSocket chat server supporting single-agent live chat with an in-memory queue, customer and agent session management, message relaying, and transcript handling.

CLI agent and interaction:

• Added agent_cli.py, a command-line interface for agents to connect to the chat server via WebSocket, send/receive messages, and manage conversation lifecycle from the terminal.

Containerization and deployment:

• Added Dockerfile to build the chat server and CLI agent into a container image, installing all dependencies and setting up the entrypoint for running the server.
• Added docker-compose.yml to orchestrate both the chat server and agent CLI containers, including health checks, port mappings, and service dependencies for local development and testing.

Dependencies:

• Added requirements.txt specifying all Python dependencies required for both the FastAPI server and the CLI agent, including fastapi, uvicorn, and websockets.